A solar cell module is one of the most important components of a solar power generation device. Sunlight irradiates to a cell from its front surface and is converted to electricity within the cell. The cell includes primary grid lines and secondary grid lines disposed on the front surface of the cell. The primary grid lines and secondary grid lines cover part of the front surface of the cell, which block part of the sunlight, and then the part of sunlight irradiating to the primary grid lines and the secondary grid lines cannot be converted into electric energy. Thus, the primary grid lines and the secondary grid lines need to be as fine as possible in order for the solar cell module to receive more sunlight. However, the primary grid lines and the secondary grid lines serve to conduct current, and in terms of resistivity, the finer the primary grid lines and the secondary grid lines are, the smaller the cross section area thereof is, which causes greater loss of electricity due to increased resistivity. Therefore, the primary grid lines and the secondary grid lines must be designed to achieve a balance between light blocking and electrical conduction, and to take the cost into consideration.